toaster-tests: tests for project config

toaster-tests: tests for project config

Add basic tests to validate the value user types
in the text box for IMAGEFS_TYPES. Added a test
case to show the checkbox get automatically selected
when user types value available in the check list.
Added a test case to verify if the check box is enabled
then the text box should also get updated accordingly.

[YOCTO #7828]

Signed-off-by: Sujith H <sujith.h@gmail.com>
Signed-off-by: Elliot Smith <elliot.smith@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>